BioMatNet Item: JOULE JOR3-CT97-0179 - Co-firing of bio-oil with simultaneous SOx and NOx reduction

[BioMatNet Database - European Commission]

JOULE JOR3-CT97-0179
Co-firing of bio-oil with simultaneous SOx and NOx reduction

To find similar Items, click on a keyword below:
JOULE/THERMIE Programme : Liquid Biofuels and Biogas : Straw : Thermochemical Conversion

	Type of Project	Shared Cost
	Contract No	JOR3-CT97-0179
	EC Contribution	1,468,340 ECU
	Start Date	01/01/1998
	Duration	36 Months

Co-firing of bio-oil with simultaneous SO_x and NO_x reduction

Objectives

This project concerns the direct injection of calcium-enriched bio-oil (BioLime) into the post combustion section of, typically, a 10 MW_e power plant, in order to desulphurise the flue gas such that emissions are below levels set by current regulations.

Specific objectives are to:

demonstrate the technique of co-firing of heavy fuel oil and BioLime at the scale of 2 MW _th;
demonstrate 90% sulphur oxides (SO_x) removal by applying BioLime;
demonstrate 50% nitric oxides (NO_x) removal by applying BioLime
demonstrate reduced CO2 output resulting from cofiring of the biomass derived BioLime
develop an optimal bio-oil modification technology (maximum calcium uptake capacity)
determine the influence of biomass type (wood, straw etc.) on the eventual BioLime quality
demonstrate that the ash characteristics remain unchanged upon co-firing of straw-derived BioLime
characterise the combustion process and emissions by monitoring concentration and temperature fields
develop a mathematical model which describes the effects of BioLime injection on SO_x/NO_x emissions and predicts the optimal operating parameters

Technical Approach

Recently, organic calcium salts such as calcium acetate, calcium magnesium acetate and calcium benzoate, have been shown to simultaneously reduce SO_x and NO_x emissions. This occurs at elevated temperatures, typical of coal and heavy fuel oil combustors, at considerably lower Ca/S ratios than in the current practice of in-situ desulphurisation (1.1:1 instead of 3:1). Biomass pyrolysis liquors offer a low cost feedstock for the preparation of such organic calcium salts. Bio-oil can easily be obtained by rapid heating of any kind of biomass in absence of oxygen, whereby subsequent condensation of the product vapours yields 70 wt% bio-oil. This bio-oil is then modified by adding lime Ca(OH)₂ in order to produce the sorbent "BioLime" that contains the organically bonded calcium. The combustion of calcium enriched bio-oil yields finely dispersed, micro-scale sized CaO that is highly reactive towards SO_x and capable of capturing more than 90% of the SO_x emission. This completely converts it to harmless gypsum, at the reduced costs of US$ 350 per ton of removed SO_x. Thus, the significant cost reduction in flue gas desulphurisation, if compared to the state-of-the-art SO_x removal technologies, constitutes the main industrial objective.

Expected Results

The results of the project should include:

development of a novel and low cost desulphurisation technology which reduces the SO_x emission by 90%
data from a desulphurisation test campaign at the scale of 2 MW_th
the production of 10 ton BioLime for flue gas desulphurisation campaigns
an injector technique for uniform distribution of the BioLime in the flue gas flow path
an information package which contains the blue print for retrofitting power stations
a computer simulation program for the prediction of power station emissions.

Contacts

Participant